Tap the blue circles to see an explanation.
| $$ \begin{aligned}\frac{21}{\sqrt{14}}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}} \frac{ 21 }{\sqrt{ 14 }} \times \frac{ \color{orangered}{\sqrt{ 14 }} }{ \color{orangered}{\sqrt{ 14 }}} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}\frac{21\sqrt{14}}{14} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}} \frac{ 21 \sqrt{ 14 } : \color{blue}{ 7 } }{ 14 : \color{blue}{ 7 } } \xlongequal{ } \\[1 em] & \xlongequal{ }\frac{3\sqrt{14}}{2}\end{aligned} $$ | |
| ① | Multiply both top and bottom by $ \color{orangered}{ \sqrt{ 14 }}$. |
| ② | In denominator we have $ \sqrt{ 14 } \cdot \sqrt{ 14 } = 14 $. |
| ③ | Divide both the top and bottom numbers by $ \color{blue}{ 7 }$. |